Local thermal probing to detect open and shorted IC interconnections

A new failure analysis technique has been developed for backside and frontside localization of open and shorted interconnections on ICs. This scanning optical microscopy technique takes advantage of the interactions between IC defects and localized heating using a focused infrared laser (lambda = 1340 nm). Images are produced by monitoring the voltage changes across a constant current supply used to power the IC as the laser beam is scanned across the sample. The method utilizes the Seebeck Effect to localize open interconnections and Thermally-Induced Voltage Alteration to detect shorts. The interaction physics describing the signal generation process and several examples demonstrating the localization of opens and shorts are described. Operational guidelines and limitations are also discussed. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.